请问C学到什么程度才能开始学板子呀
请问C学到什么程度才能开始学板子呀HAL库有个GPIO_Init函数，你能把这个函数的实现捋顺，我觉得大部分代码都可以了
/**
* @briefInitializes the GPIOx peripheral according to the specified parameters in the GPIO_Init.
* @paramGPIOx: where x can be (A..K) to select the GPIO peripheral.
* @paramGPIO_Init: pointer to a GPIO_InitTypeDef structure that contains
* the configuration information for the specified GPIO peripheral.
* @retval None
*/
void HAL_GPIO_Init(GPIO_TypeDef*GPIOx, GPIO_InitTypeDef *GPIO_Init)
{
uint32_t position = 0x00U;
uint32_t iocurrent;
uint32_t temp;
EXTI_Core_TypeDef *EXTI_CurrentCPU;
#if defined(DUAL_CORE) && defined(CORE_CM4)
EXTI_CurrentCPU = EXTI_D2; /* EXTI for CM4 CPU */
#else
EXTI_CurrentCPU = EXTI_D1; /* EXTI for CM7 CPU */
#endif
/* Check the parameters */
assert_param(IS_GPIO_ALL_INSTANCE(GPIOx));
assert_param(IS_GPIO_PIN(GPIO_Init->Pin));
assert_param(IS_GPIO_MODE(GPIO_Init->Mode));
assert_param(IS_GPIO_PULL(GPIO_Init->Pull));
/* Configure the port pins */
while (((GPIO_Init->Pin) >> position) != 0x00U)
{
/* Get current io position */
iocurrent = (GPIO_Init->Pin) & (1UL << position);
if (iocurrent != 0x00U)
{
/*--------------------- GPIO Mode Configuration ------------------------*/
/* In case of Output or Alternate function mode selection */
if ((GPIO_Init->Mode == GPIO_MODE_OUTPUT_PP) || (GPIO_Init->Mode == GPIO_MODE_AF_PP) ||
(GPIO_Init->Mode == GPIO_MODE_OUTPUT_OD) || (GPIO_Init->Mode == GPIO_MODE_AF_OD))
{
/* Check the Speed parameter */
assert_param(IS_GPIO_SPEED(GPIO_Init->Speed));
/* Configure the IO Speed */
temp = GPIOx->OSPEEDR;
temp &= ~(GPIO_OSPEEDR_OSPEED0 << (position * 2U));
temp |= (GPIO_Init->Speed << (position * 2U));
GPIOx->OSPEEDR = temp;
/* Configure the IO Output Type */
temp = GPIOx->OTYPER;
temp &= ~(GPIO_OTYPER_OT0 << position) ;
temp |= (((GPIO_Init->Mode & GPIO_OUTPUT_TYPE) >> 4U) << position);
GPIOx->OTYPER = temp;
}
/* Activate the Pull-up or Pull down resistor for the current IO */
temp = GPIOx->PUPDR;
temp &= ~(GPIO_PUPDR_PUPD0 << (position * 2U));
temp |= ((GPIO_Init->Pull) << (position * 2U));
GPIOx->PUPDR = temp;
/* In case of Alternate function mode selection */
if ((GPIO_Init->Mode == GPIO_MODE_AF_PP) || (GPIO_Init->Mode == GPIO_MODE_AF_OD))
{
/* Check the Alternate function parameters */
assert_param(IS_GPIO_AF_INSTANCE(GPIOx));
assert_param(IS_GPIO_AF(GPIO_Init->Alternate));
/* Configure Alternate function mapped with the current IO */
temp = GPIOx->AFR;
temp &= ~(0xFU << ((position & 0x07U) * 4U));
temp |= ((GPIO_Init->Alternate) << ((position & 0x07U) * 4U));
GPIOx->AFR = temp;
}
/* Configure IO Direction mode (Input, Output, Alternate or Analog) */
temp = GPIOx->MODER;
temp &= ~(GPIO_MODER_MODE0 << (position * 2U));
temp |= ((GPIO_Init->Mode & GPIO_MODE) << (position * 2U));
GPIOx->MODER = temp;
/*--------------------- EXTI Mode Configuration ------------------------*/
/* Configure the External Interrupt or event for the current IO */
if ((GPIO_Init->Mode & EXTI_MODE) == EXTI_MODE)
{
/* Enable SYSCFG Clock */
__HAL_RCC_SYSCFG_CLK_ENABLE();
temp = SYSCFG->EXTICR;
temp &= ~(0x0FUL << (4U * (position & 0x03U)));
temp |= (GPIO_GET_INDEX(GPIOx) << (4U * (position & 0x03U)));
SYSCFG->EXTICR = temp;
/* Clear EXTI line configuration */
temp = EXTI_CurrentCPU->IMR1;
temp &= ~(iocurrent);
if ((GPIO_Init->Mode & GPIO_MODE_IT) == GPIO_MODE_IT)
{
temp |= iocurrent;
}
EXTI_CurrentCPU->IMR1 = temp;
temp = EXTI_CurrentCPU->EMR1;
temp &= ~(iocurrent);
if ((GPIO_Init->Mode & GPIO_MODE_EVT) == GPIO_MODE_EVT)
{
temp |= iocurrent;
}
EXTI_CurrentCPU->EMR1 = temp;
/* Clear Rising Falling edge configuration */
temp = EXTI->RTSR1;
temp &= ~(iocurrent);
if ((GPIO_Init->Mode & RISING_EDGE) == RISING_EDGE)
{
temp |= iocurrent;
}
EXTI->RTSR1 = temp;
temp = EXTI->FTSR1;
temp &= ~(iocurrent);
if ((GPIO_Init->Mode & FALLING_EDGE) == FALLING_EDGE)
{
temp |= iocurrent;
}
EXTI->FTSR1 = temp;
}
}
position++;
}
}
用过标准库的稍微查一下相关寄存器表应该就懂了 eric2013 发表于 2022-11-22 10:14
HAL库有个GPIO_Init函数，你能把这个函数的实现捋顺，我觉得大部分代码都可以了
/**
...
我也想问这个问题，没想到楼主捷足先登了。:lol
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